Definite Purpose Starters are electrically operated switching devices specifically designed for the heating, ventilation, air conditioning and refrigeration (HVAC) industry. They are controlled by automatic thermostat control or manual pushbutton interfaces. Agency advantages supply the following brands: ①Allen-Bradley( Rockwell Automation)Series ②Square D(Schneider Electric) Series ③Eaton - Cutler Hammer (Westinghouse )Series ④SIEMENS PLC Series,Siemens CNC system ⑤Eaton moller Series